Chronic Inflammation Flashcards
Features of chronic inflammation
Delayed onset
Variable duration
Variable appearances
Limits damage, initiated repair
Can cause debilitating symptoms
How does chronic inflammation arise
- Take over from acute inflammation if resolution is not possible with a.i.
- Develops alongside acute inflammation
- Arises ‘de novo’ - without preceding acute inflammation (e.g. autoimmune conditions)
What does ‘de novo’ mean
Without preceding acute inflammation
E.g. autoimmune conditions
What cell types are present in chronic inflammation
Macrophage
Lymphocyte
Plasma cell
Eosinophil
Fibroblasts/Myofibroblasts
Giant cells (Foreign body, Langhans, Touton)
Macrophage in circulation is called…
Monocyte
Alias for ‘Macrophage’
Histiocyte
Appearance of MACROPHAGE
Large cells
Abundant, foamy cytoplasm
Slipper shaped nucleus
Contains debris/pigment
Function of MACROPHAGE
-Phagocytosis (removal of pathogen)
Antigen presentation to immune system
-Inflammatory Mediators (synthesis and release of mediators)
Controls and regulates inflammatory response
Appearance of LYMPHOCYTE
Small cells (slightly larger than RBC)
Spherical nucleus, thin rim of cytoplasm
Function of LYMPHOCYTE
T cell:
Helper- assist other inflammatory cells
Cytotoxic- destroys pathogens
B cell: Mature into plasma cells
Produced antibodies, neutralise pathogens
Appearance of PLASMA CELL
Eccentric nucleus
‘Clock-face’ chromatin
Peri-nuclear clearing by Golgi
Function of PLASMA CELL
Fully differentiated B lymphocyte
Produces antibodies
Appearance of EOSINOPHIL
Bi-lobed nucleus
Granular cytoplasm- stains RED
‘Tomato with sunglasses’
Function of EOSINOPHIL
Release of a variety of mediators
Hypersensitivity reactions (e.g. asthma)
Parasitic infection
Features of FIBROBLAST/MYOFIBROBLAST
Regeneration and repair
Types of GIANT CELLS
Foreign body giant cell
Langhans giant cell
Touton giant cel
Features of GIANT CELLS
Multinucleate cells
Fusion of multiple macrophages
‘Frustrated phagocytosis’
Features of FOREIGN BODY Giant cells
-Random scattering of nuclei
-Foreign body in the middle
E.g.) suture
Features of LANGHANS Giant cell
-Nuclei around the outside
-Horseshoe pattern
-Can be seen in tuberculosis
Features of Touton Giant cell
-Nuclei in the middle of cell
-Seen in fat necrosis
Effects of chronic inflammation
Fibrosis (deposition of collagen), e.g. liver cirrhosis
Impaired function, e.g.inflammatory bowel disease
Atrophy, e.g. atrophic gastritis
Stimulation of immune response
Explain fibrosis
Thickening / scarring of tissue
In liver…
Repeated obstruction of bile duct by gall stones
What is an impaired function as an effect of chronic inflammation
Idiopathic inflammatory bowel disease
-abdominal pain
-altered bowel motion
-weight loss
-rectal bleeding
What are the two idiopathic inflammatory bowel diseases
Crohn’s Disease
Ulcerative Colitis
Difference between ‘Crohn’s Disease’ and ‘Ulcerative Colitis’
Crohn’s Disease:
-can affect all of GI tract
-‘skip lesions’
-inflammation affects FULL THICKNESS OF BOWEL WALL
-granulomata
-less likely to have rectal bleeding
Ulcerative Colitis:
-affects LARGE BOWEL only
-continuous inflammation
-inflammation affects SUPERFICIAL BOWEL WALL only (mucosa, submucosa)
-no granulomata
-more likely to have rectal bleeding
Describe cirrhosis
End stage damage to liver
Due to alcohol, hepatitis, drugs & toxins
Features of GRANULOMA
-A collection of epithelioid histiocytes (macrophages that look like epithelial cells)
-Surrounding histiocytes
Types of granuloma
Foreign Body:
-destruction and removal of FOREIGN MATERIAL
-few lymphocytes
Immune Mediated:
-destruction and removal of PATHOGENS
-can be idiopathic
-undergoes central necrosis
-many lymphocytes
Cause of granulomatous inflammation
Foreign body reaction
Infections (e.g. mycobacterium tuberculosis/leprae)
